[Libguestfs] [PATCH nbdkit] ci: Expire artifacts after 1 week

[Richard W.M. Jones]

nbdkit uses about 1.1G of storage for artifacts.  I have personally
never looked at anything other than the artifacts of the latest failed
job, so I don't believe we need to keep these around for long.  This
commit proposes expiring (and thus deleting) artifacts after 1 week.

https://gitlab.com/nbdkit/nbdkit/-/usage_quotas

If accepted I will make a similar change for libnbd.

Martin, Dan - I don't know a lot about this and I know you've looked
into this area a lot more.  What do you think of this change?

Rich.